Online retailer seeks accounting software

We are an online specialist retailer (construction components) and are looking for an accounting program with the following requirements:

• Multi-client capable (7 clients)
• Open item management
• Online banking
• Partial standard accounting
• Partial income surplus calculation
• Paperless entry of scanned receipts
• Clear user interface
• Compliance with new data protection regulations/archiving
• Interface to existing merchandise management system
• DATEV interface
• If necessary, a separate program that automatically assigns incoming invoice numbers after scanning
• Optional asset accounting
• Network-compatible
• Windows-compatible
• Trial version for at least 30 days
• Support - program help, “user manual”
• Please specify costs, term, notice periods, etc.

This is one software workstation. The program is to be placed on the server and accessed only by one user.